Reference:
Current Limitations and Solar Flares
P. Carlqvist,
Solar physics 7(3): 377-392, June 1969.
At this point, I have no real idea what Mozina's point is suppose to be in referring to this paper, or what he thinks it is supposed to prove. Maybe it is buried in some post pages and ages ago, I don't know. So let me just tell you what I think and let it go from there. I will simply quote a specific passage from Carlqvist, which I think strikes to the heart of the paper.
Quoted from P. Carlqvist, "Current limitations and solar flares",
Solar physics 7(3): 377-392, June 1969, page 385, section 8, "Release of the Stored Energy"
Begin quote
"We have found that an energy as large as that of a flare can be stored in the twisted magnetic field of a current filament passing through the solar atmosphere. If the current density of the filament becomes sufficiently large an instability may occur, which can give rise to a high-impedance region in the filament. Since the current has to pass the potential drop of the region
UA the stored magnetic energy is released at the rate ~
UAI. The magnetic energy is then transformed into kinetic energy of the ions and electrons accelerated in the region. When the stored magnetic energy becomes dissipated the filamentary current decreases. The helical magnetic-field lines inside the filament must then be 'twisted back' and straightened."
"If the time required for the 'twist-back' of the magnetic field lines (and for the energy release) is short for the time needed for the magnetic field lines to diffuse through the filamentary plasma, the magnetic field lines can be considered 'frozen' into the plasma during the whole phase of energy release. The magnetic field will then force the filamentary plasma to rotate."
"The time constant of the diffusion for a magnetic field in a plasma of conductivity σ and with a characteristic length
lc is
td ~ μ0σlc2 (see, e.g.,
Cowling, 1957). Putting
lc equal to the radius of the filament r
0 ~ 10
5 m and σ >~ 10 S m
-1 (valid for the chromosphere and the corona) we obtain
td >~ 10
5 sec. Thus the time constant for diffusion
td seems to be much longer than the time required for the energy release (10
2 - 10
3 sec). Consequently the energy release should be intimately coupled with a rotational motion of the filamentary plasma."
"Because of the momentum of inertia of the filamentary plasma the velocity of propagation of the rotational motion along the filament is limited to the hydromagnetic velocity
V = (V'-2 + c-2)1/2, where
V' = B/(μ0ρ)1/2 and
ρ is the mass density. Hence, the minimum time of release for the whole stored energy is given by the time
tt needed for a hydromagnetic signal to move from the high-impedance region to the roots of the filament anchored in the deep layers of the solar atmosphere."
End Quote
These 4 paragraphs from Carlqvist make clear what hs is doing. The "high-impedance" region in the first paragraph is a double layer. The double layer does not ever "explode" and in fact does not even power the flare at all. The role of the double layer is to provide a potential drop which allows the magnetic field to unwind. The unwinding of the magnetic field is what imparts energy to the flare. But this process is certainly not induction, or anything like induction. It works because the magnetic field freezes to the plasma so that when the magnetic field unwinds, it drags the plasma forcibly along for the ride. So the flare is energized because a double layer forms and allows the frozen flux to power the flare; without either the double layer or the frozen flux approximation, the flare powering mechanism described here by Carlqvist would never work.
Note that induction is not involved in the process. Induction could not have been involved in the process, as Carlqvist makes clear, by showing the the diffusion time scale is much longer than the flare time scale (the same conclusion I have repeatedly posted for
Priest & Forbes, 2000). Induction would require the field to diffuse through the plasma.
Important points in this paper:
- Flares are not powered by exploding double layers.
- However, the formation of a double layer is critical to the flare process.
- The frozen flux approximation is also critical to the flare process.
- Induction is not involved in the flare process.
- The process involves one filament alone, not multiple combining filaments.
Let the comments (and corrections of there are any) begin.